+++ This bug was initially created as a clone of Bug 15734 comment 39 +++
I tried to install Mageia 5 on my new laptop (UEFI) an ASUS N551J with two graphical cards (intel and nvidia). I have tried every option mentioned in the errata (hybrid graphics). I have tried the Live KDE 64 DVD and the classical 64 DVD. Nothing works. I am now 'doomed' to use Mint, that works at once, but I like Mageia much better (if it is installable).
LiveKDE64DVD:
Sometimes at boottime (LiveDVD) I get many nouveau errors and after a while I get a KDE desktop (intel detected?). I can than install it and after reboot I sometimes can configure a user and can log in into KDE. After a few seconds everything freezes. Poweroff and poweron and than it freezes already at boottime (blank screen or with nouveau errors with sometimes I see kernel panic).
Sometimes at boottime (LiveDVD) I get less nouveau errors and it freezes already (no KDE).
I tried boot options as suggested 'optimus' and/or 'rd.blacklist=nouveau rd.blacklist=nvidia xdriver=intel' â> No effect. Still nouveau errors at boottime and/or freezes.
ClassicalKDE64DVD:
Installation works until after reboot. Same problems as with the LiveDVD.
I tried the boot options, no effect. At the point of the installer to configure the graphics, it suggested 'Intel 810 and later' and not 'use intel only' as told in the errata. Even with Intel selected I get nouveau errors at boottime, with or without boot options.
It seems a problem like mentioned in the errata with the hybrid graphics (Intel+Nvidia), but the suggested options does not work.
Linux Mint 17.1:
No problem, works at once. No errors.

A quick search found this:
https://lists.archlinux.org/pipermail/arch-general/2015-March/038729.html
My recollection is that using rd.blacklist didn't work for me, because the nouveau driver got loaded later in the boot sequence. You could try adding
blacklist nouveau
to /etc/modprobe.conf on the installed system to see if that helps.
I see in Peter's log that he is also experiencing bug 16033, although that is probably not important at this stage.

Just done some experiments on my laptop, and I need both the boot option *and* the entry in /etc/modprobe.conf to prevent the nouveau module being loaded.
Furthermore, the required boot option is "rdblacklist=nouveau", not "rd.blacklist=nouveau".

It is working now :-)
I use the boot options 'rdblacklist=nouveau nouveau.runpm=0 xdriver=intel'
nouveau.runpm=0 is a tip from doktor500, with this the LiveDVD/USB gives nouveau errors but I get at least at every boot a KDE desktop.
The same boot options I use for the installed system.
Right after install with the first boot I selected 'Safe Mode' and added 'blacklist nouveau' to /etc/modprobe.conf.
After this I get no errors and get a beautiful Mageia KDE desktop.
Thanks for all the help.

Summary:
Nouveau errors at boot time and complete desktop freeze on ASUS N551J with optimus hybrid graphics =>
Nouveau errors at boot time and complete desktop freeze on several systems with optimus hybrid graphics